Mannitol is a naturally occurring sugar alcohol (polyol) found in many plants, fruits, and vegetables. It serves as an osmotic diuretic in medicine to reduce intracranial and intraocular pressure, and as a low-calorie sweetener in foods. Chemically, it is the alditol derived from mannose with six hydroxyl groups. It exhibits a cooling effect in the mouth due to its endothermic dissolution and is non-hygroscopic. Mannitol is used in pharmaceutical tablets as a diluent and in the food industry as a sugar substitute for diabetics. It has approximately 50-70% the sweetness of sucrose but only 1.6 kcal/g. It is produced industrially by hydrogenation of fructose or extraction from seaweed.